a skateboarder traveling at 7.0 meters per second rolls to a stop at the top of a ramp in 3.0 seconds. what is the skateboarders acceleration? is 2.3m/s correct

-2.3m/s2

your numeral answer is correct (actually -7/3)

As I noted in an earlier post, since it asks for the skater's "acceleration" and he slows down to a stop ,
your answer should be expressed as a negative
so
a = -2.3

negative 2.3m/s2

yesssssssesseseseseseeseeesseseeesesesees

A skateboarder traveling with an initial velocity 9.0 meters per second, what is its final velocity, if with an acceleration of 4 m/s2 completed a time of 4.0 seconds? *

you're all wrong

MEREYI its 40 m/s

To find the skateboarder's acceleration, you can use the equation for acceleration:

Acceleration (a) = Change in Velocity (Δv) / Time Taken (Δt)

The initial velocity (u) is 7.0 meters per second (m/s), and the final velocity (v) is 0 m/s because the skateboarder comes to a stop. The time taken (Δt) is given as 3.0 seconds.

First, let's find the change in velocity (Δv):

Δv = v - u

Δv = 0 - 7.0

Δv = -7.0 m/s

Note that velocity is a vector quantity and can be negative if it is in the opposite direction of our chosen positive direction.

Next, we can substitute the values into the equation for acceleration:

a = Δv / Δt

a = -7.0 / 3.0

a ≈ -2.33 m/s^2

Therefore, the skateboarder's acceleration is approximately -2.33 m/s^2. The negative sign indicates that the acceleration is in the opposite direction to the skateboarder's initial motion.

What is the answer

I think your should get 39.32